A conventional image forming device determines whether to turn on and off a power source device depending on the condition of a failure that has occurred in the device, and whether to turn off the power source that supplies power to the entire device when an unrecoverable failure occurs, in order to save unnecessary power consumption (see Japanese Laid-Open Patent Application No. 2010-147810 (paragraphs [0068]-[0076] and FIG. 2), for example). In the applications, the “unrecoverable failure” means a failure that may be caused by heat generated by components and the like inside the device and that is difficult to overcome by the device itself, and that might damage the device. For example, an abnormal rotation and low performance of a cooling fan that are caused by a power supply error, are included. A case where a cooling fan stops due to accumulated dust or waste is as well.
However, in the above-described conventional technology, when the unrecoverable failure occurs, the entire device is always stopped because the power source that supplies power is turned off. Therefore, there is a problem that it is inconvenient for the user, as the device cannot be used until the device has recovered from the failure. The present application has an object to solve the above-described problem and to maintain the user's convenience by allowing the device to be used even when the unrecoverable failure occurs.